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elna/boot/stage14.elna
Eugen Wissner af9ad5b712 Implement enumeration
2025-10-05 11:13:24 +02:00

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(*
* This Source Code Form is subject to the terms of the Mozilla Public License,
* v. 2.0. If a copy of the MPL was not distributed with this file, You can
* obtain one at https://mozilla.org/MPL/2.0/.
*)
(* Stage 14 compiler. *)
(* - Binary minus. *)
(* - Space independent parsing. *)
(* - Label names in goto statements aren't required to begin with a dot. *)
(* - Dereferencing pointers pointing to word long data. *)
(* - Enumeration type. *)
const
symbol_builtin_name_int := "Int";
symbol_builtin_name_word := "Word";
symbol_builtin_name_pointer := "Pointer";
symbol_builtin_name_char := "Char";
symbol_builtin_name_array := "Array";
(* Every type info starts with a word describing what type it is.
PRIMITIVE_TYPE = 1
ENUMERATION_TYPE = 2
Primitive types have only type size. *)
symbol_builtin_type_int := S(1, 4);
symbol_builtin_type_word := S(1, 4);
symbol_builtin_type_pointer := S(1, 4);
symbol_builtin_type_char := S(1, 1);
symbol_builtin_type_array := S(1, 4);
(* Info objects start with a word describing its type.
TYPE_INFO = 1
PARAMETER_INFO = 2
TEMPORARY_INFO = 3
Type info has the type it belongs to. *)
symbol_type_info_int := S(1, @symbol_builtin_type_int);
symbol_type_info_word := S(1, @symbol_builtin_type_word);
symbol_type_info_pointer := S(1, @symbol_builtin_type_pointer);
symbol_type_info_char := S(1, @symbol_builtin_type_char);
symbol_type_info_array := S(1, @symbol_builtin_type_array);
var
source_code: Array;
compiler_strings: Array;
symbol_table_global: Array;
symbol_table_local: Array;
classification: Array;
(* To reserve memory just add the value of needed bytes to the memory_free_pointer_variable. *)
memory: Array;
compiler_strings_position: Pointer := @compiler_strings;
compiler_strings_length: Word := 0;
label_counter: Word := 0;
(* Points to a segment of free memory. *)
memory_free_pointer: Word := @memory;
(**
* Calculates and returns the string token length between quotes, including the
* escaping slash characters.
*
* Parameters:
* string - String token pointer.
*
* Returns the length in a0.
*)
proc _string_length(string: Word);
var
counter: Word;
begin
(* Reset the counter. *)
counter := 0;
.string_length_loop;
string := string + 1;
if _load_byte(string) <> '"' then
counter := counter + 1;
goto .string_length_loop
end;
return counter
end;
(**
* Adds a string to the global, read-only string storage.
*
* Parameters:
* string - String token.
*
* Returns the offset from the beginning of the storage to the new string in a0.
*)
proc _add_string(string: Word);
var
contents: Word;
result: Word;
current_byte: Word;
begin
contents := string + 1;
result := compiler_strings_length;
.add_string_loop;
if _load_byte(contents) <> '"' then
current_byte := _load_byte(contents);
_store_byte(current_byte, compiler_strings_position);
compiler_strings_position := compiler_strings_position + 1;
contents := contents + 1;
if current_byte <> '\\' then
compiler_strings_length := compiler_strings_length + 1
end;
goto .add_string_loop
end;
return result
end;
(**
* Reads standard input into a buffer.
*
* Parameters:
* buffer - Buffer pointer.
* size - Buffer size.
*
* Returns the amount of bytes written in a0.
*)
proc _read_file(buffer: Word, size: Word);
return _syscall(0, buffer, size, 0, 0, 0, 63)
end;
(**
* Writes to the standard output.
*
* Parameters:
* buffer - Buffer.
* size - Buffer length.
*)
proc _write_s(buffer: Word, size: Word);
begin
_syscall(1, buffer, size, 0, 0, 0, 64)
end;
(**
* Writes a number to a string buffer.
*
* Parameters:
* number - Whole number.
* output_buffer - Buffer pointer.
*
* Sets a0 to the length of the written number.
*)
proc _print_i(number: Word, output_buffer: Word);
var
local_buffer: Word;
is_negative: Word;
current_character: Word;
result: Word;
begin
local_buffer := @result + 11;
if number >= 0 then
is_negative := 0
else
number = -number;
is_negative := 1
end;
.print_i_digit10;
current_character := number % 10;
_store_byte(current_character + '0', local_buffer);
number := number / 10;
local_buffer := local_buffer + -1;
if number <> 0 then
goto .print_i_digit10
end;
if is_negative = 1 then
_store_byte('-', local_buffer);
local_buffer := local_buffer + -1
end;
result := @result + 11;
result := result + -local_buffer;
_memcpy(output_buffer, local_buffer + 1, result);
return result
end;
(**
* Writes a number to the standard output.
*
* Parameters:
* number - Whole number.
*)
proc _write_i(number: Word);
var
local_buffer: Word;
length: Word;
begin
length := _print_i(number, @local_buffer);
_write_s(@local_buffer, length)
end;
(**
* Writes a character from a0 into the standard output.
*
* Parameters:
* character - Character to write.
*)
proc _write_c(character: Word);
begin
_write_s(@character, 1)
end;
(**
* Write null terminated string.
*
* Parameters:
* string - String.
*)
proc _write_z(string: Word);
var
next_byte: Word;
begin
(* Check for 0 character. *)
next_byte := _load_byte(string);
if next_byte <> 0 then
(* Print a character. *)
_write_c(next_byte);
(* Advance the input string by one byte. *)
_write_z(string + 1)
end
end;
(**
* Detects if a0 is an uppercase character. Sets a0 to 1 if so, otherwise to 0.
*)
proc _is_upper(character: Word);
var
lhs: Word;
rhs: Word;
begin
lhs := character >= 'A';
rhs := character <= 'Z';
return lhs & rhs
end;
(**
* Detects if a0 is an lowercase character. Sets a0 to 1 if so, otherwise to 0.
*)
proc _is_lower(character: Word);
var
lhs: Word;
rhs: Word;
begin
lhs := character >= 'a';
rhs := character <= 'z';
return lhs & rhs
end;
(**
* Detects if the passed character is a 7-bit alpha character or an underscore.
*
* Paramters:
* character - Tested character.
*
* Sets a0 to 1 if the character is an alpha character or underscore, sets it to 0 otherwise.
*)
proc _is_alpha(character: Word);
var
is_upper_result: Word;
is_lower_result: Word;
is_alpha_result: Word;
is_underscore: Word;
begin
is_upper_result := _is_upper(character);
is_lower_result := _is_lower(character);
is_underscore := character = '_';
is_alpha_result := is_lower_result or is_upper_result;
return is_alpha_result or is_underscore
end;
(**
* Detects whether the passed character is a digit (a value between 0 and 9).
*
* Parameters:
* character - Exemined value.
*
* Sets a0 to 1 if it is a digit, to 0 otherwise.
*)
proc _is_digit(character: Word);
var
lhs: Word;
rhs: Word;
begin
lhs := character >= '0';
rhs := character <= '9';
return lhs & rhs
end;
proc _is_alnum(character: Word);
var
lhs: Word;
rhs: Word;
begin
lhs := _is_alpha(character);
rhs := _is_digit(character);
return lhs or rhs
end;
(**
* Parameters:
* lhs - First pointer.
* rhs - Second pointer.
* count - The length to compare.
*
* Returns 0 if memory regions are equal.
*)
proc _memcmp(lhs: Word, rhs: Word, count: Word);
var
lhs_byte: Word;
rhs_byte: Word;
result: Word;
begin
result := 0;
.memcmp_loop;
if count <> 0 then
lhs_byte := _load_byte(lhs);
rhs_byte := _load_byte(rhs);
result := lhs_byte + -rhs_byte;
lhs := lhs + 1;
rhs := rhs + 1;
count := count + -1;
if result = 0 then
goto .memcmp_loop
end
end;
return result
end;
(**
* Copies memory.
*
* Parameters:
* destination - Destination.
* source - Source.
* count - Size.
*
* Returns the destination.
*)
proc _memcpy(destination: Word, source: Word, count: Word);
var
current_byte: Word;
begin
.memcpy_loop;
if count <> 0 then
current_byte := _load_byte(source);
_store_byte(current_byte, destination);
destination := destination + 1;
source := source + 1;
count := count + -1;
goto .memcpy_loop
end;
return destination
end;
proc _compile_integer_literal();
var
integer_token: Word;
integer_length: Word;
token_kind: Word;
begin
_write_z("\tli t0, \0");
integer_token := _lexer_global_get_start();
integer_length := _lexer_global_get_end() + -integer_token;
_write_s(integer_token, integer_length);
_lexer_skip_token();
_write_c('\n')
end;
proc _compile_character_literal();
var
character: Word;
token_kind: Word;
character_length: Word;
begin
character := _lexer_global_get_start();
character_length := _lexer_global_get_end() + -character;
_write_z("\tli t0, \0");
_write_s(character, character_length);
_write_c('\n');
_lexer_skip_token()
end;
proc _compile_variable_expression();
var
name: Word;
lookup_result: Word;
name_token: Word;
begin
name := _lexer_global_get_start();
name_token := _lexer_global_get_end() + -name;
lookup_result := _symbol_table_lookup(@symbol_table_global, name, name_token);
if lookup_result <> 0 then
_compile_enumeration_value(lookup_result)
else
_compile_designator();
_write_z("\tlw t0, (t0)\n\0")
end
end;
(**
* Compiled take address expression, starting with an "@" sign.
*)
proc _compile_address_expression();
begin
_lexer_skip_token();
_compile_designator()
end;
(**
* Compile unary negation, "-" sign.
*)
proc _compile_negate_expression();
begin
_lexer_skip_token();
_compile_term();
_write_z("\tneg t0, t0\n\0")
end;
(* Compile unary negation, "~" sign. *)
proc _compile_not_expression();
var
token_kind: Word;
begin
_lexer_read_token(@token_kind);
_lexer_skip_token();
_compile_term();
_write_z("\tnot t0, t0\n\0")
end;
proc _compile_string_literal();
var
token_kind: Word;
token_start: Word;
length: Word;
offset: Word;
begin
_lexer_read_token(@token_kind);
token_start := _lexer_global_get_start();
length := _string_length(token_start);
offset := _add_string(token_start);
_lexer_skip_token();
_write_z("\tla t0, strings\n\0");
_write_z("\tli t1, \0");
_write_i(offset);
_write_c('\n');
_write_z("\tadd t0, t0, t1\n\0")
end;
proc _compile_term();
var
current_character: Word;
token_kind: Word;
begin
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_character() then
_compile_character_literal()
elsif token_kind = _lexer_token_kind_string() then
_compile_string_literal()
elsif token_kind = _lexer_token_kind_integer() then
_compile_integer_literal()
elsif token_kind = _lexer_token_kind_at() then
_compile_address_expression()
elsif token_kind = _lexer_token_kind_minus() then
_compile_negate_expression()
elsif token_kind = _lexer_token_kind_not() then
_compile_not_expression()
elsif token_kind = _lexer_token_kind_identifier() then
current_character := _lexer_global_get_start();
current_character := _load_byte(current_character);
(* This is a call if the statement starts with an underscore. *)
if current_character = '_' then
_compile_call();
_write_z("\tmv t0, a0\n\0")
else
_compile_variable_expression()
end
end
end;
proc _compile_binary_rhs();
begin
(* Save the value of the left expression on the stack. *)
_write_z("\tsw t0, 64(sp)\n\0");
_compile_term();
(* Load the left expression from the stack; *)
_write_z("\tlw t1, 64(sp)\n\0")
end;
proc _compile_expression();
var
token_kind: Word;
begin
_compile_term();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_plus() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tadd t0, t0, t1\n\0")
elsif token_kind = _lexer_token_kind_minus() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tsub t0, t1, t0\n\0");
elsif token_kind = _lexer_token_kind_multiplication() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tmul t0, t0, t1\n\0")
elsif token_kind = _lexer_token_kind_and() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tand t0, t0, t1\n\0")
elsif token_kind = _lexer_token_kind_or() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tor t0, t0, t1\n\0")
elsif token_kind = _lexer_token_kind_xor() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\txor t0, t0, t1\n\0")
elsif token_kind = _lexer_token_kind_equals() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\txor t0, t0, t1\n\tseqz t0, t0\n\0")
elsif token_kind = _lexer_token_kind_remainder() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\trem t0, t1, t0\n\0")
elsif token_kind = _lexer_token_kind_division() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tdiv t0, t1, t0\n\0")
elsif token_kind = _lexer_token_kind_less_than() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tslt t0, t1, t0\n\0")
elsif token_kind = _lexer_token_kind_greater_than() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tslt t0, t0, t1\n\0")
elsif token_kind = _lexer_token_kind_less_equal() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tslt t0, t0, t1\n\txori t0, t0, 1\n\0")
elsif token_kind = _lexer_token_kind_not_equal() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\txor t0, t0, t1\n\tsnez t0, t0\n\0")
elsif token_kind = _lexer_token_kind_greater_equal() then
_lexer_skip_token();
_compile_binary_rhs();
(* Execute the operation. *)
_write_z("\tslt t0, t1, t0\n\txori t0, t0, 1\n\0")
end;
.compile_expression_end;
end;
proc _compile_call();
var
name_length: Word;
name: Word;
argument_count: Word;
stack_offset: Word;
token_kind: Word;
begin
_lexer_read_token(@token_kind);
name := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -name;
argument_count := 0;
(* Skip the identifier and left paren. *)
_lexer_skip_token();
_lexer_read_token(@token_kind);
_lexer_skip_token();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_right_paren() then
goto .compile_call_finalize
end;
.compile_call_loop;
_compile_expression();
(* Save the argument on the stack. *)
_write_z("\tsw t0, \0");
(* Calculate the stack offset: 116 - (4 * argument_counter) *)
stack_offset := argument_count * 4;
_write_i(116 + -stack_offset);
_write_z("(sp)\n\0");
(* Add one to the argument counter. *)
argument_count := argument_count + 1;
_lexer_read_token(@token_kind);
if token_kind <> _lexer_token_kind_comma() then
goto .compile_call_finalize
end;
_lexer_skip_token();
goto .compile_call_loop;
.compile_call_finalize;
(* Load the argument from the stack. *)
if argument_count <> 0 then
(* Decrement the argument counter. *)
argument_count := argument_count + -1;
_write_z("\tlw a\0");
_write_i(argument_count);
_write_z(", \0");
(* Calculate the stack offset: 116 - (4 * argument_counter) *)
stack_offset := argument_count * 4;
_write_i(116 + -stack_offset);
_write_z("(sp)\n\0");
goto .compile_call_finalize
end;
.compile_call_end;
_write_z("\tcall \0");
_write_s(name, name_length);
_write_c('\n');
(* Skip the right paren. *)
_lexer_read_token(@token_kind);
_lexer_skip_token()
end;
proc _compile_goto();
var
next_token: Word;
next_length: Word;
token_kind: Word;
begin
_lexer_skip_token();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_dot() then
_lexer_skip_token();
_lexer_read_token(@token_kind)
end;
next_token := _lexer_global_get_start();
next_length := _lexer_global_get_end() + -next_token;
_write_z("\tj .\0");
_write_s(next_token, next_length);
_lexer_skip_token()
end;
proc _compile_local_designator(symbol: Word);
var
variable_offset: Word;
begin
_write_z("\taddi t0, sp, \0");
variable_offset := _parameter_info_get_offset(symbol);
_write_i(variable_offset);
_write_c('\n');
_lexer_skip_token()
end;
proc _compile_global_designator();
var
name: Word;
token_kind: Word;
token_length: Word;
begin
_write_z("\tla t0, \0");
_lexer_read_token(@token_kind);
name := _lexer_global_get_start();
token_length := _lexer_global_get_end() + -name;
_write_s(name, token_length);
_lexer_skip_token();
_write_c('\n')
end;
proc _compile_enumeration_value(symbol: Word);
var
enumeration_type: Word;
members: Word;
members_length: Word;
token_type: Word;
value_name: Word;
name_length: Word;
member_name: Word;
member_length: Word;
counter: Word;
begin
enumeration_type := _type_info_get_type(symbol);
members := _enumeration_type_get_members(enumeration_type);
members_length := _enumeration_type_get_length(enumeration_type);
(* Skip enumeration type name and dot. Read the enumeration value. *)
_lexer_skip_token();
_lexer_read_token(@token_type);
_lexer_skip_token();
_lexer_read_token(@token_type);
value_name := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -value_name;
_lexer_skip_token();
counter := 1;
.compile_enumeration_value_members;
if members_length > 0 then
member_name := _load_word(members);
member_length := _load_word(members + 4);
if _lexer_compare_keyword(value_name, name_length, member_name, member_length) = 0 then
members_length := members_length + -1;
members := members + 8;
counter := counter + 1;
goto .compile_enumeration_value_members
end;
_write_z("\tli t0, \0");
_write_i(counter);
_write_c('\n')
end
end;
proc _compile_designator();
var
name_token: Word;
lookup_result: Word;
token_kind: Word;
name: Word;
begin
_lexer_read_token(@token_kind);
name := _lexer_global_get_start();
name_token := _lexer_global_get_end() + -name;
lookup_result := _symbol_table_lookup(@symbol_table_local, name, name_token);
if lookup_result <> 0 then
_compile_local_designator(lookup_result)
else
_compile_global_designator()
end;
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_hat() then
_lexer_skip_token();
_write_z("\tlw t0, (t0)\n\0")
end
end;
proc _compile_assignment();
var
token_kind: Word;
begin
_compile_designator();
(* Save the assignee address on the stack. *)
_write_z("\tsw t0, 60(sp)\n\0");
(* Skip the assignment sign (:=) with surrounding whitespaces. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
(* Compile the assignment. *)
_compile_expression();
_write_z("\tlw t1, 60(sp)\n\tsw t0, (t1)\n\0")
end;
proc _compile_return_statement();
var
token_kind: Word;
begin
(* Skip "return" keyword and whitespace after it. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
_compile_expression();
_write_z("\tmv a0, t0\n\0")
end;
(**
* Writes a label, .Ln, where n is a unique number.
*
* Parameters:
* counter - Label counter.
*)
proc _write_label(counter: Word);
begin
_write_z(".L\0");
_write_i(counter)
end;
proc _compile_condition(after_end_label: Word);
var
condition_label: Word;
token_kind: Word;
begin
(* Compile condition. *)
_compile_expression();
(* Skip " then" with newline. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
(* condition_label is the label in front of the next elsif condition or end. *)
condition_label := label_counter;
label_counter := label_counter + 1;
_write_z("\tbeqz t0, \0");
_write_label(condition_label);
_write_c('\n');
_compile_statement_list();
_write_z("\tj \0");
_write_label(after_end_label);
_write_c('\n');
_write_label(condition_label);
_write_z(":\n\0")
end;
proc _compile_if();
var
after_end_label: Word;
condition_label: Word;
token_kind: Word;
begin
(* Skip "if ". *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
after_end_label := label_counter;
label_counter := label_counter + 1;
_compile_condition(after_end_label);
.compile_if_loop;
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_else() then
_lexer_skip_token();
_compile_statement_list()
elsif token_kind = _lexer_token_kind_elsif() then
_lexer_skip_token();
_compile_condition(after_end_label);
goto .compile_if_loop
end;
_lexer_skip_token();
_write_label(after_end_label);
_write_z(":\n\0")
end;
proc _compile_label_declaration();
var
label_token: Word;
token_kind: Word;
name: Word;
begin
(* Skip the dot. *)
_lexer_skip_token();
_lexer_read_token(@token_kind);
name := _lexer_global_get_start();
label_token := _lexer_global_get_end() + -name;
_write_c('.');
_write_s(name, label_token);
_write_z(":\n\0");
_lexer_skip_token()
end;
proc _compile_statement();
var
current_byte: Word;
token_kind: Word;
begin
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_goto() then
_compile_goto()
elsif token_kind = _lexer_token_kind_if() then
_compile_if()
elsif token_kind = _lexer_token_kind_return() then
_compile_return_statement()
elsif token_kind = _lexer_token_kind_dot() then
_compile_label_declaration()
elsif token_kind = _lexer_token_kind_identifier() then
current_byte := _lexer_global_get_start();
current_byte := _load_byte(current_byte);
(* This is a call if the statement starts with an underscore. *)
if current_byte = '_' then
_compile_call()
else
_compile_assignment()
end
end;
_write_c('\n')
end;
proc _compile_statement_list();
var
token_kind: Word;
begin
_skip_empty_lines();
_compile_statement();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_semicolon() then
_lexer_skip_token();
_compile_statement_list()
end;
_skip_empty_lines()
end;
(**
* Writes a regster name to the standard output.
*
* Parameters:
* register_character - Register character.
* register_number - Register number.
*)
proc _write_register(register_character: Word, register_number: Word);
begin
_write_c(register_character);
_write_c(register_number + '0')
end;
proc _type_get_kind(this: Word);
return _load_word(this)
end;
proc _type_set_kind(this: Word, value: Word);
begin
_store_word(value, this)
end;
proc _type_get_size(this: Word);
return _load_word(this + 4)
end;
proc _type_set_size(this: Word, value: Word);
begin
_store_word(value, this + 4)
end;
proc _enumeration_type_get_members(this: Word);
return _load_word(this + 8)
end;
proc _enumeration_type_set_members(this: Word, value: Word);
begin
_store_word(value, this + 8)
end;
proc _enumeration_type_get_length(this: Word);
return _load_word(this + 12)
end;
proc _enumeration_type_set_length(this: Word, value: Word);
begin
_store_word(value, this + 12)
end;
(**
* Reads and creates enumeration type representation.
*
* record
* type_kind: Word;
* size: Word;
* members: StringArray;
* length: Word
* end;
*
* Returns enumeration type description.
*)
proc _read_type_enumeration();
var
token_kind: Word;
enumeration_name: Word;
name_length: Word;
memory_start: Word;
member_count: Word;
result: Word;
begin
_lexer_skip_token();
memory_start := memory_free_pointer;
member_count := 0;
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_right_paren() then
goto .read_type_enumeration_end
end;
.read_type_enumeration_loop;
member_count := member_count + 1;
enumeration_name := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -enumeration_name;
_store_word(enumeration_name, memory_free_pointer);
memory_free_pointer := memory_free_pointer + 4;
_store_word(name_length, memory_free_pointer);
memory_free_pointer := memory_free_pointer + 4;
(* Skip the identifier. *)
_lexer_skip_token();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_comma() then
_lexer_skip_token();
_lexer_read_token(@token_kind);
goto .read_type_enumeration_loop
end;
.read_type_enumeration_end;
_lexer_skip_token();
(* The resulting structure is 16 bytes long. *)
result := memory_free_pointer;
memory_free_pointer := memory_free_pointer + 16;
(* ENUMERATION_TYPE is 2. *)
_type_set_kind(result, 2);
_type_set_size(result, 4);
_enumeration_type_set_members(result, memory_start);
_enumeration_type_set_length(result, member_count);
return _type_info_create(result)
end;
proc _read_type_expression();
var
token_kind: Word;
type_name: Word;
name_length: Word;
result: Word;
begin
result := 0;
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_identifier() then
(* Named type. *)
type_name := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -type_name;
result := _symbol_table_lookup(@symbol_table_global, type_name, name_length);
result := _type_info_get_type(result);
_lexer_skip_token()
elsif token_kind = _lexer_token_kind_left_paren() then
result := _read_type_enumeration()
end;
return result
end;
proc _type_info_get_type(this: Word);
return _load_word(this + 4)
end;
(**
* Parameters:
* parameter_index - Parameter index.
*)
proc _parameter_info_create(parameter_index: Word);
var
offset: Word;
current_word: Word;
result: Word;
begin
result := memory_free_pointer;
current_word := result;
(* 2 is INFO_PARAMETER *)
_store_word(2, current_word);
current_word := current_word + 4;
(* Calculate the stack offset: 88 - (4 * parameter_counter) *)
offset := parameter_index * 4;
_store_word(88 + -offset, current_word);
memory_free_pointer := current_word + 4;
return result
end;
proc _parameter_info_get_offset(this: Word);
begin
this := this + 4;
return _load_word(this)
end;
proc _type_info_create(type_representation: Word);
var
result: Word;
current_word: Word;
begin
result := memory_free_pointer;
current_word := result;
(* 1 is INFO_TYPE *)
_store_word(1, current_word);
current_word := current_word + 4;
_store_word(type_representation, current_word);
memory_free_pointer := current_word + 4;
return result
end;
(**
* Parameters:
* temporary_index - Parameter index.
*)
proc _temporary_info_create(temporary_index: Word);
var
offset: Word;
current_word: Word;
result: Word;
begin
result := memory_free_pointer;
current_word := result;
(* 3 is INFO_TEMPORARY *)
_store_word(3, current_word);
current_word := current_word + 4;
(* Calculate the stack offset: 4 * variable_counter. *)
_store_word(temporary_index * 4, current_word);
memory_free_pointer := current_word + 4;
return result
end;
proc _temporary_info_get_offset(this: Word);
begin
this := this + 4;
return _load_word(this)
end;
(**
* Parameters:
* parameter_index - Parameter index.
*)
proc _read_procedure_parameter(parameter_index: Word);
var
name_length: Word;
info: Word;
name_position: Word;
token_kind: Word;
begin
(* Read the parameter name. *)
_lexer_read_token(@token_kind);
name_position := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -name_position;
_lexer_skip_token();
(* Skip colon and space in front of the type expression. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
_read_type_expression();
_write_z("\tsw a\0");
_write_i(parameter_index);
_write_z(", \0");
info := _parameter_info_create(parameter_index);
_symbol_table_enter(@symbol_table_local, name_position, name_length, info);
info := _parameter_info_get_offset(info);
_write_i(info);
_write_z("(sp)\n\0")
end;
proc _read_procedure_parameters();
var
parameter_counter: Word;
token_kind: Word;
begin
(* Skip open paren. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
parameter_counter := 0;
.compile_procedure_prologue_skip;
_lexer_read_token(@token_kind);
if token_kind <> _lexer_token_kind_right_paren() then
_read_procedure_parameter(parameter_counter);
parameter_counter := parameter_counter + 1;
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_comma() then
_lexer_skip_token();
goto .compile_procedure_prologue_skip
end
end;
(* Skip close paren. *)
_lexer_skip_token()
end;
(**
* Parameters:
* variable_index - Variable index.
*)
proc _read_procedure_temporary(variable_index: Word);
var
name_length: Word;
info: Word;
name_position: Word;
token_kind: Word;
begin
_lexer_read_token(@token_kind);
name_position := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -name_position;
_lexer_skip_token();
(* Read and skip variable name, colon and the space *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
_read_type_expression();
info := _temporary_info_create(variable_index);
_symbol_table_enter(@symbol_table_local, name_position, name_length, info);
(* Skip semicolon and newline after the variable declaration *)
_lexer_read_token(@token_kind);
_lexer_skip_token()
end;
proc _read_procedure_temporaries();
var
temporary_counter: Word;
token_kind: Word;
begin
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_var() then
_lexer_skip_token();
temporary_counter := 0;
.read_local_variables_loop;
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_identifier() then
_read_procedure_temporary(temporary_counter);
temporary_counter := temporary_counter + 1;
goto .read_local_variables_loop
end
end
end;
proc _compile_procedure();
var
name_pointer: Word;
name_length: Word;
token_kind: Word;
begin
(* Skip "proc ". *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
(* Clear local symbol table. *)
_store_word(0, @symbol_table_local);
_lexer_read_token(@token_kind);
name_pointer := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -name_pointer;
(* Write .type _procedure_name, @function. *)
_write_z(".type \0");
_write_s(name_pointer, name_length);
_write_z(", @function\n\0");
(* Write procedure label, _procedure_name: *)
_write_s(name_pointer, name_length);
_write_z(":\n\0");
(* Skip procedure name. *)
_lexer_skip_token();
_write_z("\taddi sp, sp, -128\n\tsw ra, 124(sp)\n\tsw s0, 120(sp)\n\taddi s0, sp, 128\n\0");
_read_procedure_parameters();
(* Skip semicolon and newline. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
_read_procedure_temporaries();
(* Skip semicolon, "begin" and newline. *)
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_begin() then
_lexer_skip_token();
_compile_statement_list()
elsif token_kind = _lexer_token_kind_return() then
_compile_return_statement()
end;
(* Write the epilogue. *)
_write_z("\tlw ra, 124(sp)\n\tlw s0, 120(sp)\n\taddi sp, sp, 128\n\tret\n\0");
(* Skip the "end" keyword, semicolon and newline. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
_lexer_read_token(@token_kind);
_lexer_skip_token()
end;
(**
* Skips comments.
*)
proc _skip_empty_lines();
var
token_kind: Word;
begin
.skip_empty_lines_rerun;
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_comment() then
_lexer_skip_token();
goto .skip_empty_lines_rerun
end
end;
(**
* Compile global variable initializer.
*)
proc _compile_global_initializer();
var
current_byte: Word;
length: Word;
token_kind: Word;
token_start: Word;
begin
_lexer_read_token(@token_kind);
token_start := _lexer_global_get_start();
current_byte := _load_byte(token_start);
if token_kind = _lexer_token_kind_string() then
_write_z("\n\t.word strings + \0");
length := _string_length(token_start);
_add_string(token_start);
_write_i();
(* Skip the quoted string. *)
_lexer_skip_token();
goto .compile_global_initializer_end
elsif current_byte = 'S' then
(* Skip "S(". *)
_lexer_skip_token();
_lexer_read_token(@token_kind);
_lexer_skip_token();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_right_paren() then
goto .compile_global_initializer_closing
end;
goto .compile_global_initializer_loop
elsif token_kind = _lexer_token_kind_at() then
(* Skip @. *)
_lexer_skip_token();
_write_z("\n\t.word \0");
_lexer_read_token(@token_kind);
token_start := _lexer_global_get_start();
_write_s(token_start, _lexer_global_get_end() + -token_start);
_lexer_skip_token();
goto .compile_global_initializer_end
elsif token_kind = _lexer_token_kind_integer() then
_write_z("\n\t.word \0");
_write_s(token_start, _lexer_global_get_end() + -token_start);
_lexer_skip_token();
goto .compile_global_initializer_end
end;
.compile_global_initializer_loop;
_compile_global_initializer();
_lexer_read_token(@token_kind);
if token_kind <> _lexer_token_kind_right_paren() then
(* Skip comma and whitespace after it. *)
_lexer_skip_token();
goto .compile_global_initializer_loop
end;
.compile_global_initializer_closing;
(* Skip ")" *)
_lexer_skip_token();
.compile_global_initializer_end
end;
proc _compile_constant_declaration();
var
name: Word;
name_length: Word;
token_kind: Word;
begin
name := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -name;
_write_z(".type \0");
_write_s(name, name_length);
_write_z(", @object\n\0");
_write_s(name, name_length);
_write_c(':');
(* Skip the constant name with assignment sign and surrounding whitespaces. *)
_lexer_skip_token();
_lexer_read_token(@token_kind);
_lexer_skip_token();
_compile_global_initializer();
(* Skip semicolon and newline. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
_write_c('\n')
end;
proc _compile_type_declaration();
var
token_kind: Word;
type_name: Word;
name_length: Word;
type_info: Word;
begin
type_name := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -type_name;
_lexer_skip_token();
_lexer_read_token(@token_kind);
_lexer_skip_token();
type_info := _read_type_expression();
_symbol_table_enter(@symbol_table_global, type_name, name_length, type_info);
_lexer_read_token(@token_kind);
_lexer_skip_token()
end;
proc _compile_type_part();
var
token_kind: Word;
begin
_skip_empty_lines();
_lexer_read_token(@token_kind);
if token_kind <> _lexer_token_kind_type() then
goto .compile_type_part_end
end;
_lexer_skip_token();
.compile_type_part_loop;
_skip_empty_lines();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_identifier() then
_compile_type_declaration();
goto .compile_type_part_loop
end;
.compile_type_part_end
end;
proc _compile_const_part();
var
token_kind: Word;
begin
_skip_empty_lines();
_lexer_read_token(@token_kind);
if token_kind <> _lexer_token_kind_const() then
goto .compile_const_part_end
end;
(* Skip "const" with the newline after it. *)
_lexer_skip_token();
_write_z(".section .rodata # Compiled from const section.\n\n\0");
.compile_const_part_loop;
_skip_empty_lines();
(* If the character at the line beginning is not indentation,
it is probably the next code section. *)
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_identifier() then
_compile_constant_declaration();
goto .compile_const_part_loop
end;
.compile_const_part_end
end;
proc _compile_variable_declaration();
var
name: Word;
name_length: Word;
token_kind: Word;
begin
_lexer_read_token(@token_kind);
name := _lexer_global_get_start();
name_length := _lexer_global_get_end() + -name;
_write_z(".type \0");
_write_s(name, name_length);
_write_z(", @object\n\0");
_write_s(name, name_length);
_write_c(':');
(* Skip the variable name and colon with space before the type. *)
_lexer_skip_token();
_lexer_read_token(@token_kind);
_lexer_skip_token();
_read_type_expression();
_lexer_read_token(@token_kind);
if token_kind <> _lexer_token_kind_assignment() then
(* Else we assume this is a zeroed 81920 bytes big array. *)
_write_z(" .zero 81920\0")
else
(* Skip the assignment sign with surrounding whitespaces. *)
_lexer_skip_token();
_compile_global_initializer();
_lexer_read_token(@token_kind)
end;
(* Skip semicolon and newline. *)
_lexer_read_token(@token_kind);
_lexer_skip_token();
_write_c('\n')
end;
proc _compile_var_part();
var
token_kind: Word;
begin
_lexer_read_token(@token_kind);
if token_kind <> _lexer_token_kind_var() then
goto .compile_var_part_end
end;
(* Skip "var" and newline. *)
_lexer_skip_token();
_write_z(".section .data\n\0");
.compile_var_part_loop;
_skip_empty_lines();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_identifier() then
_compile_variable_declaration();
goto .compile_var_part_loop
end;
.compile_var_part_end
end;
(**
* Process the source code and print the generated code.
*)
proc _compile_module();
var
token_kind: Word;
begin
_compile_type_part();
_compile_const_part();
_skip_empty_lines();
_compile_var_part();
_write_z(".section .text\n\n\0");
_write_z(".type _syscall, @function\n_syscall:\n\tmv a7, a6\n\tecall\n\tret\n\n\0");
_write_z(".type _load_byte, @function\n_load_byte:\n\tlb a0, (a0)\nret\n\n\0");
_write_z(".type _load_word, @function\n_load_word:\n\tlw a0, (a0)\nret\n\n\0");
_write_z(".type _store_byte, @function\n_store_byte:\n\tsb a0, (a1)\nret\n\n\0");
_write_z(".type _store_word, @function\n_store_word:\n\tsw a0, (a1)\nret\n\n\0");
.compile_module_loop;
_skip_empty_lines();
_lexer_read_token(@token_kind);
if token_kind = _lexer_token_kind_proc() then
_compile_procedure();
goto .compile_module_loop
end
end;
proc _compile();
var
compiler_strings_copy: Word;
compiler_strings_end: Word;
current_byte: Word;
begin
_write_z(".globl _start\n\n\0");
_compile_module();
_write_z(".section .rodata\n.type strings, @object\nstrings: .ascii \0");
_write_c('"');
compiler_strings_copy := @compiler_strings;
compiler_strings_end := compiler_strings_position;
.compile_loop;
if compiler_strings_copy < compiler_strings_end then
current_byte := _load_byte(compiler_strings_copy);
compiler_strings_copy := compiler_strings_copy + 1;
_write_c(current_byte);
goto .compile_loop
end;
_write_c('"');
_write_c('\n')
end;
(**
* Terminates the program. a0 contains the return code.
*
* Parameters:
* a0 - Status code.
*)
proc _exit();
begin
_syscall(0, 0, 0, 0, 0, 0, 93)
end;
(**
* Looks for a symbol in the given symbol table.
*
* Parameters:
* symbol_table - Symbol table.
* symbol_name - Symbol name pointer.
* name_length - Symbol name length.
*
* Returns the symbol pointer or 0 in a0.
*)
proc _symbol_table_lookup(symbol_table: Word, symbol_name: Word, name_length: Word);
var
result: Word;
symbol_table_length: Word;
current_name: Word;
current_length: Word;
begin
result := 0;
(* The first word in the symbol table is its length, get it. *)
symbol_table_length := _load_word(symbol_table);
(* Go to the first symbol position. *)
symbol_table := symbol_table + 4;
.symbol_table_lookup_loop;
if symbol_table_length = 0 then
goto .symbol_table_lookup_end
end;
(* Symbol name pointer and length. *)
current_name := _load_word(symbol_table);
current_length := _load_word(symbol_table + 4);
(* If lengths don't match, exit and return nil. *)
if name_length <> current_length then
goto .symbol_table_lookup_repeat
end;
(* If names don't match, exit and return nil. *)
if _memcmp(symbol_name, current_name, name_length) <> 0 then
goto .symbol_table_lookup_repeat
end;
(* Otherwise, the symbol is found. *)
result := _load_word(symbol_table + 8);
goto .symbol_table_lookup_end;
.symbol_table_lookup_repeat;
symbol_table := symbol_table + 12;
symbol_table_length := symbol_table_length + -1;
goto .symbol_table_lookup_loop;
.symbol_table_lookup_end;
return result
end;
(**
* Inserts a symbol into the table.
*
* Parameters:
* symbol_table - Symbol table.
* symbol_name - Symbol name pointer.
* name_length - Symbol name length.
* symbol - Symbol pointer.
*)
proc _symbol_table_enter(symbol_table: Word, symbol_name: Word, name_length: Word, symbol: Word);
var
table_length: Word;
symbol_pointer: Word;
begin
(* The first word in the symbol table is its length, get it. *)
table_length := _load_word(symbol_table);
(* Calculate the offset for the new symbol. *)
symbol_pointer := table_length * 12;
symbol_pointer := symbol_pointer + 4;
symbol_pointer := symbol_table + symbol_pointer;
_store_word(symbol_name, symbol_pointer);
symbol_pointer := symbol_pointer + 4;
_store_word(name_length, symbol_pointer);
symbol_pointer := symbol_pointer + 4;
_store_word(symbol, symbol_pointer);
(* Increment the symbol table length. *)
table_length := table_length + 1;
_store_word(table_length, symbol_table)
end;
proc _symbol_table_build();
begin
(* Set the table length to 0. *)
_store_word(0, @symbol_table_global);
(* Enter built-in symbols. *)
_symbol_table_enter(@symbol_table_global, symbol_builtin_name_int, 3, @symbol_type_info_int);
_symbol_table_enter(@symbol_table_global, symbol_builtin_name_word, 4, @symbol_type_info_word);
_symbol_table_enter(@symbol_table_global, symbol_builtin_name_pointer, 7, @symbol_type_info_pointer);
_symbol_table_enter(@symbol_table_global, symbol_builtin_name_char, 4, @symbol_type_info_char);
_symbol_table_enter(@symbol_table_global, symbol_builtin_name_array, 5, @symbol_type_info_array)
end;
(**
* Classification table assigns each possible character to a group (class). All
* characters of the same group a handled equivalently.
*
* Transition = record
* action: TransitionAction;
* next_state: TransitionState
* end;
*)
proc _lexer_class_invalid();
return 1
end;
proc _lexer_class_digit();
return 2
end;
proc _lexer_class_alpha();
return 3
end;
proc _lexer_class_space();
return 4
end;
proc _lexer_class_colon();
return 5
end;
proc _lexer_class_equals();
return 6
end;
proc _lexer_class_left_paren();
return 7
end;
proc _lexer_class_right_paren();
return 8
end;
proc _lexer_class_asterisk();
return 9
end;
proc _lexer_class_backslash();
return 10
end;
proc _lexer_class_single();
return 11
end;
proc _lexer_class_hex();
return 12
end;
proc _lexer_class_zero();
return 13
end;
proc _lexer_class_x();
return 14
end;
proc _lexer_class_eof();
return 15
end;
proc _lexer_class_dot();
return 16
end;
proc _lexer_class_minus();
return 17
end;
proc _lexer_class_single_quote();
return 18
end;
proc _lexer_class_double_quote();
return 19
end;
proc _lexer_class_greater();
return 20
end;
proc _lexer_class_less();
return 21
end;
proc _lexer_class_other();
return 22
end;
proc _lexer_state_start();
return 1
end;
proc _lexer_state_colon();
return 2
end;
proc _lexer_state_identifier();
return 3
end;
proc _lexer_state_decimal();
return 4
end;
proc _lexer_state_leading_zero();
return 5
end;
proc _lexer_state_greater();
return 6
end;
proc _lexer_state_minus();
return 7
end;
proc _lexer_state_left_paren();
return 8
end;
proc _lexer_state_less();
return 9
end;
proc _lexer_state_dot();
return 10
end;
proc _lexer_state_comment();
return 11
end;
proc _lexer_state_closing_comment();
return 12
end;
proc _lexer_state_character();
return 13
end;
proc _lexer_state_character_escape();
return 14
end;
proc _lexer_state_string();
return 15
end;
proc _lexer_state_string_escape();
return 16
end;
proc _lexer_state_end();
return 17
end;
proc _lexer_action_none();
return 1
end;
proc _lexer_action_accumulate();
return 2
end;
proc _lexer_action_skip();
return 3
end;
proc _lexer_action_single();
return 4
end;
proc _lexer_action_eof();
return 5
end;
proc _lexer_action_finalize();
return 6
end;
proc _lexer_action_composite();
return 7
end;
proc _lexer_action_key_id();
return 8
end;
proc _lexer_action_integer();
return 9
end;
proc _lexer_action_delimited();
return 10
end;
(**
* Assigns some value to at array index.
*
* Parameters:
* array - Array pointer.
* index - Index (word offset into the array).
* data - Data to assign.
*)
proc _assign_at(array: Word, index: Word, data: Word);
var
target: Word;
begin
target := index + -1;
target := target * 4;
target := array + target;
_store_word(data, target)
end;
proc _get_at(array: Word, index: Word);
var
target: Word;
begin
target := index + -1;
target := target * 4;
target := array + target;
return _load_word(target)
end;
(**
* Initializes the array with character classes.
*)
proc _lexer_classifications();
var
code: Word;
begin
_assign_at(@classification, 1, _lexer_class_eof());
_assign_at(@classification, 2, _lexer_class_invalid());
_assign_at(@classification, 3, _lexer_class_invalid());
_assign_at(@classification, 4, _lexer_class_invalid());
_assign_at(@classification, 5, _lexer_class_invalid());
_assign_at(@classification, 6, _lexer_class_invalid());
_assign_at(@classification, 7, _lexer_class_invalid());
_assign_at(@classification, 8, _lexer_class_invalid());
_assign_at(@classification, 9, _lexer_class_invalid());
_assign_at(@classification, 10, _lexer_class_space());
_assign_at(@classification, 11, _lexer_class_space());
_assign_at(@classification, 12, _lexer_class_invalid());
_assign_at(@classification, 13, _lexer_class_invalid());
_assign_at(@classification, 14, _lexer_class_space());
_assign_at(@classification, 15, _lexer_class_invalid());
_assign_at(@classification, 16, _lexer_class_invalid());
_assign_at(@classification, 17, _lexer_class_invalid());
_assign_at(@classification, 18, _lexer_class_invalid());
_assign_at(@classification, 19, _lexer_class_invalid());
_assign_at(@classification, 20, _lexer_class_invalid());
_assign_at(@classification, 21, _lexer_class_invalid());
_assign_at(@classification, 22, _lexer_class_invalid());
_assign_at(@classification, 23, _lexer_class_invalid());
_assign_at(@classification, 24, _lexer_class_invalid());
_assign_at(@classification, 25, _lexer_class_invalid());
_assign_at(@classification, 26, _lexer_class_invalid());
_assign_at(@classification, 27, _lexer_class_invalid());
_assign_at(@classification, 28, _lexer_class_invalid());
_assign_at(@classification, 29, _lexer_class_invalid());
_assign_at(@classification, 30, _lexer_class_invalid());
_assign_at(@classification, 31, _lexer_class_invalid());
_assign_at(@classification, 32, _lexer_class_invalid());
_assign_at(@classification, 33, _lexer_class_space());
_assign_at(@classification, 34, _lexer_class_single());
_assign_at(@classification, 35, _lexer_class_double_quote());
_assign_at(@classification, 36, _lexer_class_other());
_assign_at(@classification, 37, _lexer_class_other());
_assign_at(@classification, 38, _lexer_class_single());
_assign_at(@classification, 39, _lexer_class_single());
_assign_at(@classification, 40, _lexer_class_single_quote());
_assign_at(@classification, 41, _lexer_class_left_paren());
_assign_at(@classification, 42, _lexer_class_right_paren());
_assign_at(@classification, 43, _lexer_class_asterisk());
_assign_at(@classification, 44, _lexer_class_single());
_assign_at(@classification, 45, _lexer_class_single());
_assign_at(@classification, 46, _lexer_class_minus());
_assign_at(@classification, 47, _lexer_class_dot());
_assign_at(@classification, 48, _lexer_class_single());
_assign_at(@classification, 49, _lexer_class_zero());
_assign_at(@classification, 50, _lexer_class_digit());
_assign_at(@classification, 51, _lexer_class_digit());
_assign_at(@classification, 52, _lexer_class_digit());
_assign_at(@classification, 53, _lexer_class_digit());
_assign_at(@classification, 54, _lexer_class_digit());
_assign_at(@classification, 55, _lexer_class_digit());
_assign_at(@classification, 56, _lexer_class_digit());
_assign_at(@classification, 57, _lexer_class_digit());
_assign_at(@classification, 58, _lexer_class_digit());
_assign_at(@classification, 59, _lexer_class_colon());
_assign_at(@classification, 60, _lexer_class_single());
_assign_at(@classification, 61, _lexer_class_less());
_assign_at(@classification, 62, _lexer_class_equals());
_assign_at(@classification, 63, _lexer_class_greater());
_assign_at(@classification, 64, _lexer_class_other());
_assign_at(@classification, 65, _lexer_class_single());
_assign_at(@classification, 66, _lexer_class_alpha());
_assign_at(@classification, 67, _lexer_class_alpha());
_assign_at(@classification, 68, _lexer_class_alpha());
_assign_at(@classification, 69, _lexer_class_alpha());
_assign_at(@classification, 70, _lexer_class_alpha());
_assign_at(@classification, 71, _lexer_class_alpha());
_assign_at(@classification, 72, _lexer_class_alpha());
_assign_at(@classification, 73, _lexer_class_alpha());
_assign_at(@classification, 74, _lexer_class_alpha());
_assign_at(@classification, 75, _lexer_class_alpha());
_assign_at(@classification, 76, _lexer_class_alpha());
_assign_at(@classification, 77, _lexer_class_alpha());
_assign_at(@classification, 78, _lexer_class_alpha());
_assign_at(@classification, 79, _lexer_class_alpha());
_assign_at(@classification, 80, _lexer_class_alpha());
_assign_at(@classification, 81, _lexer_class_alpha());
_assign_at(@classification, 82, _lexer_class_alpha());
_assign_at(@classification, 83, _lexer_class_alpha());
_assign_at(@classification, 84, _lexer_class_alpha());
_assign_at(@classification, 85, _lexer_class_alpha());
_assign_at(@classification, 86, _lexer_class_alpha());
_assign_at(@classification, 87, _lexer_class_alpha());
_assign_at(@classification, 88, _lexer_class_alpha());
_assign_at(@classification, 89, _lexer_class_alpha());
_assign_at(@classification, 90, _lexer_class_alpha());
_assign_at(@classification, 91, _lexer_class_alpha());
_assign_at(@classification, 92, _lexer_class_single());
_assign_at(@classification, 93, _lexer_class_backslash());
_assign_at(@classification, 94, _lexer_class_single());
_assign_at(@classification, 95, _lexer_class_single());
_assign_at(@classification, 96, _lexer_class_alpha());
_assign_at(@classification, 97, _lexer_class_other());
_assign_at(@classification, 98, _lexer_class_hex());
_assign_at(@classification, 99, _lexer_class_hex());
_assign_at(@classification, 100, _lexer_class_hex());
_assign_at(@classification, 101, _lexer_class_hex());
_assign_at(@classification, 102, _lexer_class_hex());
_assign_at(@classification, 103, _lexer_class_hex());
_assign_at(@classification, 104, _lexer_class_alpha());
_assign_at(@classification, 105, _lexer_class_alpha());
_assign_at(@classification, 106, _lexer_class_alpha());
_assign_at(@classification, 107, _lexer_class_alpha());
_assign_at(@classification, 108, _lexer_class_alpha());
_assign_at(@classification, 109, _lexer_class_alpha());
_assign_at(@classification, 110, _lexer_class_alpha());
_assign_at(@classification, 111, _lexer_class_alpha());
_assign_at(@classification, 112, _lexer_class_alpha());
_assign_at(@classification, 113, _lexer_class_alpha());
_assign_at(@classification, 114, _lexer_class_alpha());
_assign_at(@classification, 115, _lexer_class_alpha());
_assign_at(@classification, 116, _lexer_class_alpha());
_assign_at(@classification, 117, _lexer_class_alpha());
_assign_at(@classification, 118, _lexer_class_alpha());
_assign_at(@classification, 119, _lexer_class_alpha());
_assign_at(@classification, 120, _lexer_class_alpha());
_assign_at(@classification, 121, _lexer_class_x());
_assign_at(@classification, 122, _lexer_class_alpha());
_assign_at(@classification, 123, _lexer_class_alpha());
_assign_at(@classification, 124, _lexer_class_other());
_assign_at(@classification, 125, _lexer_class_single());
_assign_at(@classification, 126, _lexer_class_other());
_assign_at(@classification, 127, _lexer_class_single());
_assign_at(@classification, 128, _lexer_class_invalid());
code := 129;
(* Set the remaining 129 - 256 bytes to transitionClassOther. *)
.create_classification_loop;
_assign_at(@classification, code, _lexer_class_other());
code := code + 1;
if code < 257 then
goto .create_classification_loop
end
end;
proc _lexer_get_transition(current_state: Word, character_class: Word);
var
transition_table: Word;
row_position: Word;
column_position: Word;
target: Word;
begin
(* Each state is 8 bytes long (2 words: action and next state).
There are 22 character classes, so a transition row 8 * 22 = 176 bytes long. *)
row_position := current_state + -1;
row_position := row_position * 176;
column_position := character_class + -1;
column_position := column_position * 8;
target := _lexer_get_transition_table() + row_position;
return target + column_position
end;
(**
* Parameters:
* current_state - First index into transitions table.
* character_class - Second index into transitions table.
* action - Action to assign.
* next_state - Next state to assign.
*)
proc _lexer_set_transition(current_state: Word, character_class: Word, action: Word, next_state: Word);
var
transition: Word;
begin
transition := _lexer_get_transition(current_state, character_class);
_lexer_transition_set_action(transition, action);
_lexer_transition_set_state(transition, next_state)
end;
(* Sets same action and state transition for all character classes in one transition row. *)
(**
* Parameters:
* current_state - Current state (Transition state enumeration).
* default_action - Default action (Callback).
* next_state - Next state (Transition state enumeration).
*)
proc _lexer_default_transition(current_state: Word, default_action: Word, next_state: Word);
begin
_lexer_set_transition(current_state, _lexer_class_invalid(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_digit(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_alpha(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_space(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_colon(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_equals(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_left_paren(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_right_paren(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_asterisk(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_backslash(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_single(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_hex(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_zero(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_x(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_eof(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_dot(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_minus(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_single_quote(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_double_quote(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_greater(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_less(), default_action, next_state);
_lexer_set_transition(current_state, _lexer_class_other(), default_action, next_state)
end;
(**
* The transition table describes transitions from one state to another, given
* a symbol (character class).
*
* The table has m rows and n columns, where m is the amount of states and n is
* the amount of classes. So given the current state and a classified character
* the table can be used to look up the next state.
*)
proc _lexer_transitions();
begin
(* Start state. *)
_lexer_set_transition(_lexer_state_start(), _lexer_class_invalid(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_start(), _lexer_class_digit(), _lexer_action_accumulate(), _lexer_state_decimal());
_lexer_set_transition(_lexer_state_start(), _lexer_class_alpha(), _lexer_action_accumulate(), _lexer_state_identifier());
_lexer_set_transition(_lexer_state_start(), _lexer_class_space(), _lexer_action_skip(), _lexer_state_start());
_lexer_set_transition(_lexer_state_start(), _lexer_class_colon(), _lexer_action_accumulate(), _lexer_state_colon());
_lexer_set_transition(_lexer_state_start(), _lexer_class_equals(), _lexer_action_single(), _lexer_state_end());
_lexer_set_transition(_lexer_state_start(), _lexer_class_left_paren(), _lexer_action_accumulate(), _lexer_state_left_paren());
_lexer_set_transition(_lexer_state_start(), _lexer_class_right_paren(), _lexer_action_single(), _lexer_state_end());
_lexer_set_transition(_lexer_state_start(), _lexer_class_asterisk(), _lexer_action_single(), _lexer_state_end());
_lexer_set_transition(_lexer_state_start(), _lexer_class_backslash(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_start(), _lexer_class_single(), _lexer_action_single(), _lexer_state_end());
_lexer_set_transition(_lexer_state_start(), _lexer_class_hex(), _lexer_action_accumulate(), _lexer_state_identifier());
_lexer_set_transition(_lexer_state_start(), _lexer_class_zero(), _lexer_action_accumulate(), _lexer_state_leading_zero());
_lexer_set_transition(_lexer_state_start(), _lexer_class_x(), _lexer_action_accumulate(), _lexer_state_identifier());
_lexer_set_transition(_lexer_state_start(), _lexer_class_eof(), _lexer_action_eof(), _lexer_state_end());
_lexer_set_transition(_lexer_state_start(), _lexer_class_dot(), _lexer_action_single(), _lexer_state_end());
_lexer_set_transition(_lexer_state_start(), _lexer_class_minus(), _lexer_action_accumulate(), _lexer_state_minus());
_lexer_set_transition(_lexer_state_start(), _lexer_class_single_quote(), _lexer_action_accumulate(), _lexer_state_character());
_lexer_set_transition(_lexer_state_start(), _lexer_class_double_quote(), _lexer_action_accumulate(), _lexer_state_string());
_lexer_set_transition(_lexer_state_start(), _lexer_class_greater(), _lexer_action_accumulate(), _lexer_state_greater());
_lexer_set_transition(_lexer_state_start(), _lexer_class_less(), _lexer_action_accumulate(), _lexer_state_less());
_lexer_set_transition(_lexer_state_start(), _lexer_class_other(), _lexer_action_none(), _lexer_state_end());
(* Colon state. *)
_lexer_default_transition(_lexer_state_colon(), _lexer_action_finalize(), _lexer_state_end());
_lexer_set_transition(_lexer_state_colon(), _lexer_class_equals(), _lexer_action_composite(), _lexer_state_end());
(* Identifier state. *)
_lexer_default_transition(_lexer_state_identifier(), _lexer_action_key_id(), _lexer_state_end());
_lexer_set_transition(_lexer_state_identifier(), _lexer_class_digit(), _lexer_action_accumulate(), _lexer_state_identifier());
_lexer_set_transition(_lexer_state_identifier(), _lexer_class_alpha(), _lexer_action_accumulate(), _lexer_state_identifier());
_lexer_set_transition(_lexer_state_identifier(), _lexer_class_hex(), _lexer_action_accumulate(), _lexer_state_identifier());
_lexer_set_transition(_lexer_state_identifier(), _lexer_class_zero(), _lexer_action_accumulate(), _lexer_state_identifier());
_lexer_set_transition(_lexer_state_identifier(), _lexer_class_x(), _lexer_action_accumulate(), _lexer_state_identifier());
(* Decimal state. *)
_lexer_default_transition(_lexer_state_decimal(), _lexer_action_integer(), _lexer_state_end());
_lexer_set_transition(_lexer_state_decimal(), _lexer_class_digit(), _lexer_action_accumulate(), _lexer_state_decimal());
_lexer_set_transition(_lexer_state_decimal(), _lexer_class_alpha(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_decimal(), _lexer_class_hex(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_decimal(), _lexer_class_zero(), _lexer_action_accumulate(), _lexer_state_decimal());
_lexer_set_transition(_lexer_state_decimal(), _lexer_class_x(), _lexer_action_none(), _lexer_state_end());
(* Leading zero. *)
_lexer_default_transition(_lexer_state_leading_zero(), _lexer_action_integer(), _lexer_state_end());
_lexer_set_transition(_lexer_state_leading_zero(), _lexer_class_digit(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_leading_zero(), _lexer_class_alpha(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_leading_zero(), _lexer_class_hex(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_leading_zero(), _lexer_class_zero(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_leading_zero(), _lexer_class_x(), _lexer_action_none(), _lexer_state_dot());
(* Greater state. *)
_lexer_default_transition(_lexer_state_greater(), _lexer_action_finalize(), _lexer_state_end());
_lexer_set_transition(_lexer_state_greater(), _lexer_class_equals(), _lexer_action_composite(), _lexer_state_end());
(* Minus state. *)
_lexer_default_transition(_lexer_state_minus(), _lexer_action_finalize(), _lexer_state_end());
_lexer_set_transition(_lexer_state_minus(), _lexer_class_greater(), _lexer_action_composite(), _lexer_state_end());
(* Left paren state. *)
_lexer_default_transition(_lexer_state_left_paren(), _lexer_action_finalize(), _lexer_state_end());
_lexer_set_transition(_lexer_state_left_paren(), _lexer_class_asterisk(), _lexer_action_accumulate(), _lexer_state_comment());
(* Less state. *)
_lexer_default_transition(_lexer_state_less(), _lexer_action_finalize(), _lexer_state_end());
_lexer_set_transition(_lexer_state_less(), _lexer_class_equals(), _lexer_action_composite(), _lexer_state_end());
_lexer_set_transition(_lexer_state_less(), _lexer_class_greater(), _lexer_action_composite(), _lexer_state_end());
(* Hexadecimal after 0x. *)
_lexer_default_transition(_lexer_state_dot(), _lexer_action_finalize(), _lexer_state_end());
_lexer_set_transition(_lexer_state_dot(), _lexer_class_dot(), _lexer_action_composite(), _lexer_state_end());
(* Comment. *)
_lexer_default_transition(_lexer_state_comment(), _lexer_action_accumulate(), _lexer_state_comment());
_lexer_set_transition(_lexer_state_comment(), _lexer_class_asterisk(), _lexer_action_accumulate(), _lexer_state_closing_comment());
_lexer_set_transition(_lexer_state_comment(), _lexer_class_eof(), _lexer_action_none(), _lexer_state_end());
(* Closing comment. *)
_lexer_default_transition(_lexer_state_closing_comment(), _lexer_action_accumulate(), _lexer_state_comment());
_lexer_set_transition(_lexer_state_closing_comment(), _lexer_class_invalid(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_closing_comment(), _lexer_class_right_paren(), _lexer_action_delimited(), _lexer_state_end());
_lexer_set_transition(_lexer_state_closing_comment(), _lexer_class_asterisk(), _lexer_action_accumulate(), _lexer_state_closing_comment());
_lexer_set_transition(_lexer_state_closing_comment(), _lexer_class_eof(), _lexer_action_none(), _lexer_state_end());
(* Character. *)
_lexer_default_transition(_lexer_state_character(), _lexer_action_accumulate(), _lexer_state_character());
_lexer_set_transition(_lexer_state_character(), _lexer_class_invalid(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_character(), _lexer_class_eof(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_character(), _lexer_class_single_quote(), _lexer_action_delimited(), _lexer_state_end());
_lexer_set_transition(_lexer_state_character(), _lexer_class_backslash(), _lexer_action_accumulate(), _lexer_state_character_escape());
(* Escape sequence in a character. *)
_lexer_default_transition(_lexer_state_character_escape(), _lexer_action_accumulate(), _lexer_state_character());
_lexer_set_transition(_lexer_state_character_escape(), _lexer_class_invalid(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_character_escape(), _lexer_class_eof(), _lexer_action_none(), _lexer_state_end());
(* String. *)
_lexer_default_transition(_lexer_state_string(), _lexer_action_accumulate(), _lexer_state_string());
_lexer_set_transition(_lexer_state_string(), _lexer_class_invalid(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_string(), _lexer_class_eof(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_string(), _lexer_class_double_quote(), _lexer_action_delimited(), _lexer_state_end());
_lexer_set_transition(_lexer_state_string(), _lexer_class_backslash(), _lexer_action_accumulate(), _lexer_state_string_escape());
(* Escape sequence in a string. *)
_lexer_default_transition(_lexer_state_string_escape(), _lexer_action_accumulate(), _lexer_state_string());
_lexer_set_transition(_lexer_state_string_escape(), _lexer_class_invalid(), _lexer_action_none(), _lexer_state_end());
_lexer_set_transition(_lexer_state_string_escape(), _lexer_class_eof(), _lexer_action_none(), _lexer_state_end())
end;
(**
* Transition table is saved after character classification table.
* Each character entry is 1 word long and there are 256 characters.
* 1024 = 256 * 4
*)
proc _lexer_get_transition_table();
return @classification + 1024
end;
(**
* Lexer state is saved after the transition tables.
* Each transition table entry is 8 bytes long. The table has 16 rows (transition states)
* and 22 columns (character classes), so 2992 = 8 * 17 * 22.
*)
proc _lexer_global_state();
return _lexer_get_transition_table() + 2992
end;
(**
* Gets pointer to the token start.
*)
proc _lexer_global_get_start();
var
target: Word;
begin
target := _lexer_global_state() + 4;
return _load_word(target)
end;
(**
* Sets pointer to the token start.
*)
proc _lexer_global_set_start(new_start: Word);
var
target: Word;
begin
target := _lexer_global_state() + 4;
_store_word(new_start, target)
end;
(**
* Gets pointer to the token end.
*)
proc _lexer_global_get_end();
var
target: Word;
begin
target := _lexer_global_state() + 8;
return _load_word(target)
end;
(**
* Sets pointer to the token end.
*)
proc _lexer_global_set_end(new_start: Word);
var
target: Word;
begin
target := _lexer_global_state() + 8;
_store_word(new_start, target)
end;
proc _lexer_transition_get_action(transition: Word);
return _load_word(transition)
end;
proc _lexer_transition_set_action(transition: Word, action: Word);
begin
_store_word(action, transition)
end;
proc _lexer_transition_get_state(transition: Word);
return _load_word(transition + 4)
end;
proc _lexer_transition_set_state(transition: Word, state: Word);
begin
_store_word(state, transition + 4)
end;
(**
* Resets the lexer state for reading the next token.
*)
proc _lexer_reset();
var
state: Word;
begin
(* Transition start state is 1. *)
state := _lexer_global_state();
_store_word(_lexer_state_start(), state);
state := _lexer_global_get_start();
_lexer_global_set_end(state)
end;
(**
* One time lexer initialization.
*)
proc _lexer_initialize();
begin
_lexer_classifications();
_lexer_transitions();
_lexer_global_set_start(@source_code);
_lexer_global_set_end(@source_code)
end;
proc _lexer_next_transition();
var
current_character: Word;
character_class: Word;
current_state: Word;
begin
current_character := _lexer_global_get_end();
current_character := _load_byte(current_character);
character_class := _get_at(@classification, current_character + 1);
current_state := _lexer_global_state();
current_state := _load_word(current_state);
return _lexer_get_transition(current_state, character_class)
end;
proc _lexer_token_kind_identifier();
return 1
end;
proc _lexer_token_kind_const();
return 2
end;
proc _lexer_token_kind_var();
return 3
end;
proc _lexer_token_kind_proc();
return 4
end;
proc _lexer_token_kind_type();
return 5
end;
proc _lexer_token_kind_begin();
return 6
end;
proc _lexer_token_kind_end();
return 7
end;
proc _lexer_token_kind_if();
return 8
end;
proc _lexer_token_kind_then();
return 9
end;
proc _lexer_token_kind_else();
return 10
end;
proc _lexer_token_kind_elsif();
return 11
end;
proc _lexer_token_kind_while();
return 12
end;
proc _lexer_token_kind_do();
return 13
end;
proc _lexer_token_kind_extern();
return 14
end;
proc _lexer_token_kind_record();
return 15
end;
proc _lexer_token_kind_union();
return 16
end;
proc _lexer_token_kind_true();
return 17
end;
proc _lexer_token_kind_false();
return 18
end;
proc _lexer_token_kind_nil();
return 19
end;
proc _lexer_token_kind_and();
return 20
end;
proc _lexer_token_kind_or();
return 21
end;
proc _lexer_token_kind_xor();
return 22
end;
proc _lexer_token_kind_pipe();
return 23
end;
proc _lexer_token_kind_not();
return 24
end;
proc _lexer_token_kind_return();
return 24
end;
proc _lexer_token_kind_module();
return 25
end;
proc _lexer_token_kind_program();
return 26
end;
proc _lexer_token_kind_import();
return 27
end;
proc _lexer_token_kind_cast();
return 28
end;
proc _lexer_token_kind_defer();
return 29
end;
proc _lexer_token_kind_case();
return 30
end;
proc _lexer_token_kind_of();
return 31
end;
proc _lexer_token_kind_trait();
return 32
end;
proc _lexer_token_kind_left_paren();
return 33
end;
proc _lexer_token_kind_right_paren();
return 34
end;
proc _lexer_token_kind_left_square();
return 35
end;
proc _lexer_token_kind_right_square();
return 36
end;
proc _lexer_token_kind_shift_left();
return 37
end;
proc _lexer_token_kind_shift_right();
return 38
end;
proc _lexer_token_kind_greater_equal();
return 39
end;
proc _lexer_token_kind_less_equal();
return 40
end;
proc _lexer_token_kind_greater_than();
return 41
end;
proc _lexer_token_kind_less_than();
return 42
end;
proc _lexer_token_kind_not_equal();
return 43
end;
proc _lexer_token_kind_equals();
return 44
end;
proc _lexer_token_kind_semicolon();
return 45
end;
proc _lexer_token_kind_dot();
return 46
end;
proc _lexer_token_kind_comma();
return 47
end;
proc _lexer_token_kind_plus();
return 48
end;
proc _lexer_token_kind_arrow();
return 49
end;
proc _lexer_token_kind_minus();
return 50
end;
proc _lexer_token_kind_multiplication();
return 51
end;
proc _lexer_token_kind_division();
return 52
end;
proc _lexer_token_kind_remainder();
return 53
end;
proc _lexer_token_kind_assignment();
return 54
end;
proc _lexer_token_kind_colon();
return 55
end;
proc _lexer_token_kind_hat();
return 56
end;
proc _lexer_token_kind_at();
return 57
end;
proc _lexer_token_kind_comment();
return 58
end;
proc _lexer_token_kind_string();
return 59
end;
proc _lexer_token_kind_character();
return 60
end;
proc _lexer_token_kind_integer();
return 61
end;
proc _lexer_token_kind_word();
return 62
end;
proc _lexer_token_kind_goto();
return 63
end;
proc _lexer_token_kind_eof();
return 64
end;
proc _lexer_compare_keyword(lhs_pointer: Word, lhs_length: Word, rhs_pointer: Word, rhs_length: Word);
var
result: Word;
begin
result := 0;
if lhs_length = rhs_length then
result := _memcmp(lhs_pointer, rhs_pointer, lhs_length) = 0
end;
return result
end;
proc _lexer_classify_keyword(position_start: Word, position_end: Word);
var
result: Word;
token_length: Word;
begin
result := _lexer_token_kind_identifier();
token_length := position_end + -position_start;
if _lexer_compare_keyword(position_start, token_length, "const", 5) = 1 then
result := _lexer_token_kind_const()
elsif _lexer_compare_keyword(position_start, token_length, "var", 3) = 1 then
result := _lexer_token_kind_var()
elsif _lexer_compare_keyword(position_start, token_length, "proc", 4) = 1 then
result := _lexer_token_kind_proc()
elsif _lexer_compare_keyword(position_start, token_length, "type", 4) = 1 then
result := _lexer_token_kind_type()
elsif _lexer_compare_keyword(position_start, token_length, "begin", 5) = 1 then
result := _lexer_token_kind_begin()
elsif _lexer_compare_keyword(position_start, token_length, "end", 3) = 1 then
result := _lexer_token_kind_end()
elsif _lexer_compare_keyword(position_start, token_length, "return", 6) = 1 then
result := _lexer_token_kind_return()
elsif _lexer_compare_keyword(position_start, token_length, "goto", 4) = 1 then
result := _lexer_token_kind_goto()
elsif _lexer_compare_keyword(position_start, token_length, "if", 2) = 1 then
result := _lexer_token_kind_if()
elsif _lexer_compare_keyword(position_start, token_length, "while", 5) = 1 then
result := _lexer_token_kind_while()
elsif _lexer_compare_keyword(position_start, token_length, "then", 4) = 1 then
result := _lexer_token_kind_then()
elsif _lexer_compare_keyword(position_start, token_length, "else", 4) = 1 then
result := _lexer_token_kind_else()
elsif _lexer_compare_keyword(position_start, token_length, "elsif", 5) = 1 then
result := _lexer_token_kind_elsif()
elsif _lexer_compare_keyword(position_start, token_length, "or", 2) = 1 then
result := _lexer_token_kind_or()
elsif _lexer_compare_keyword(position_start, token_length, "xor", 2) = 1 then
result := _lexer_token_kind_xor()
end;
return result
end;
proc _lexer_classify_finalize(start_position: Word);
var
character: Word;
result: Word;
begin
result := 0;
character := _load_byte(start_position);
if character = ':' then
result := _lexer_token_kind_colon()
elsif character = '.' then
result := _lexer_token_kind_dot()
elsif character = '(' then
result := _lexer_token_kind_left_paren()
elsif character = '-' then
result := _lexer_token_kind_minus()
elsif character = '<' then
result := _lexer_token_kind_less_than()
elsif character = '>' then
result := _lexer_token_kind_greater_than()
end;
return result
end;
proc _lexer_classify_single(start_position: Word);
var
character: Word;
result: Word;
begin
result := 0;
character := _load_byte(start_position);
if character = ';' then
result := _lexer_token_kind_semicolon()
elsif character = ',' then
result := _lexer_token_kind_comma()
elsif character = ')' then
result := _lexer_token_kind_right_paren()
elsif character = '@' then
result := _lexer_token_kind_at()
elsif character = '~' then
result := _lexer_token_kind_not()
elsif character = '&' then
result := _lexer_token_kind_and()
elsif character = '+' then
result := _lexer_token_kind_plus()
elsif character = '*' then
result := _lexer_token_kind_multiplication()
elsif character = '=' then
result := _lexer_token_kind_equals()
elsif character = '%' then
result := _lexer_token_kind_remainder()
elsif character = '/' then
result := _lexer_token_kind_division()
elsif character = '.' then
result := _lexer_token_kind_dot()
elsif character = '^' then
result := _lexer_token_kind_hat()
end;
return result
end;
proc _lexer_classify_composite(start_position: Word, one_before_last: Word);
var
first_character: Word;
last_character: Word;
result: Word;
begin
first_character := _load_byte(start_position);
last_character := _load_byte(one_before_last);
if first_character = ':' then
result := _lexer_token_kind_assignment()
elsif first_character = '<' then
if last_character = '=' then
result := _lexer_token_kind_less_equal()
elsif last_character = '>' then
result := _lexer_token_kind_not_equal()
end
elsif first_character = '>' then
if last_character = '=' then
result := _lexer_token_kind_greater_equal()
end
end;
return result
end;
proc _lexer_classify_delimited(start_position: Word, end_position: Word);
var
token_length: Word;
delimiter: Word;
result: Word;
begin
token_length := end_position + -start_position;
delimiter := _load_byte(start_position);
if delimiter = '(' then
result := _lexer_token_kind_comment()
elsif delimiter = '\'' then
result := _lexer_token_kind_character()
elsif delimiter = '"' then
result := _lexer_token_kind_string()
end;
return result
end;
proc _lexer_classify_integer(start_position: Word, end_position: Word);
begin
return _lexer_token_kind_integer()
end;
proc _lexer_execute_action(action_to_perform: Word, kind: Word);
var
position_start: Word;
position_end: Word;
intermediate: Word;
begin
position_start := _lexer_global_get_start();
position_end := _lexer_global_get_end();
if action_to_perform = _lexer_action_none() then
elsif action_to_perform = _lexer_action_accumulate() then
_lexer_global_set_end(position_end + 1)
elsif action_to_perform = _lexer_action_skip() then
_lexer_global_set_start(position_start + 1);
_lexer_global_set_end(position_end + 1)
elsif action_to_perform = _lexer_action_single() then
_lexer_global_set_end(position_end + 1);
intermediate := _lexer_classify_single(position_start);
_store_word(intermediate, kind)
elsif action_to_perform = _lexer_action_eof() then
intermediate := _lexer_token_kind_eof();
_store_word(intermediate, kind)
elsif action_to_perform = _lexer_action_finalize() then
intermediate := _lexer_classify_finalize(position_start);
_store_word(intermediate, kind)
elsif action_to_perform = _lexer_action_composite() then
_lexer_global_set_end(position_end + 1);
intermediate := _lexer_classify_composite(position_start, position_end);
_store_word(intermediate, kind)
elsif action_to_perform = _lexer_action_key_id() then
intermediate := _lexer_classify_keyword(position_start, position_end);
_store_word(intermediate, kind)
elsif action_to_perform = _lexer_action_integer() then
intermediate := _lexer_classify_integer(position_start, position_end);
_store_word(intermediate, kind)
elsif action_to_perform = _lexer_action_delimited() then
_lexer_global_set_end(position_end + 1);
intermediate := _lexer_classify_delimited(position_start, position_end + 1);
_store_word(intermediate, kind)
end;
end;
proc _lexer_execute_transition(kind: Word);
var
next_transition: Word;
next_state: Word;
global_state: Word;
action_to_perform: Word;
begin
next_transition := _lexer_next_transition();
next_state := _lexer_transition_get_state(next_transition);
action_to_perform := _lexer_transition_get_action(next_transition);
global_state := _lexer_global_state();
_store_word(next_state, global_state);
_lexer_execute_action(action_to_perform, kind);
return next_state
end;
proc _lexer_advance_token(kind: Word);
begin
if _lexer_execute_transition(kind) <> _lexer_state_end() then
_lexer_advance_token(kind)
end
end;
(**
* Reads the next token and writes its type into the address in the kind parameter.
*)
proc _lexer_read_token(kind: Word);
begin
_lexer_reset();
_lexer_advance_token(kind)
end;
(**
* Advances the token stream past the last read token.
*)
proc _lexer_skip_token();
var
old_end: Word;
begin
old_end := _lexer_global_get_end();
_lexer_global_set_start(old_end)
end;
(*
* Entry point.
*)
proc _start();
var
last_read: Word;
offset: Word;
begin
_lexer_initialize();
_symbol_table_build();
(* Read the source from the standard input. *)
offset := @source_code;
.start_read;
(* Second argument is buffer size. Modifying update the source_code definition. *)
last_read := _read_file(offset, 81920);
if last_read > 0 then
offset := offset + last_read;
goto .start_read
end;
_compile();
_exit(0)
end;
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